Methods
# static exports.getAccurateAnnualEquatorialAberration(jd, coords) → {EquatorialCoordinatesCorrection}
Accurate annual aberration for equatorial coordinates
It is due to the orbital motion of the Earth around the barycenter of the Solar system.
This is the high-accuracy Ron-Vondrak expression for aberration. See AA p153.
Parameters:
| Name | Type | Description |
|---|---|---|
jd |
JulianDay
|
The julian day |
coords |
EquatorialCoordinates
|
The equatorial coordinates |
EquatorialCoordinatesCorrection
# static exports.getAge(jd) → {JulianDay}
The age of the Moon cycle (0 = New Moon, MOON_SYNODIC_PERIOD/2 = Full Moon).
This is a low-accuracy age of the moon, using the average moon synodic period.
Parameters:
| Name | Type | Description |
|---|---|---|
jd |
JulianDay
|
The julian day |
# static exports.getAgeName(jd) → {MoonPhase}
The age name of the Moon cycle (New, WaxingCresent, FirstQuarter etc)
Parameters:
| Name | Type | Description |
|---|---|---|
jd |
JulianDay
|
The julian day |
The moon phase name
# static exports.getAnnualEclipticAberration(jd, coords) → {EclipticCoordinatesCorrection}
Ecliptic (annual) aberration
It is due to the orbital motion of the Earth around the barycenter of the Solar system.
Parameters:
| Name | Type | Description |
|---|---|---|
jd |
JulianDay
|
The julian day |
coords |
EclipticCoordinates
|
The ecliptic coordinates |
The coordinates corrections in Arcsecond
EclipticCoordinatesCorrection
# static exports.getAnnualEquatorialAberration(jd, coords) → {EclipticCoordinatesCorrection}
Equatorial (annual) aberration
It is due to the orbital motion of the Earth around the barycenter of the Solar system.
See getAccurateAnnualEquatorialAberration for high-accuracy algorithm, taking into account the total velocity of the Earth
relative to the barycenter of the solar system.
See AA p 152, Equ 23.3
Parameters:
| Name | Type | Description |
|---|---|---|
jd |
JulianDay
|
The julian day |
coords |
EquatorialCoordinates
|
The equatorial coordinates |
- See:
-
- {getAccurateAnnualEquatorialAberration}
The coordinates corrections in ArcSeconds
EclipticCoordinatesCorrection
# static exports.getApparentGeocentricEquatorialCoordinates(jd) → {EquatorialCoordinates}
Apparent geocentric equatorial coordinates, that is corrected for nutation
Parameters:
| Name | Type | Description |
|---|---|---|
jd |
JulianDay
|
The julian day |
- See:
-
- getApparentEquatorialCoordinates
# static exports.getArgumentOfLatitude(jd) → {Degree}
Argument of latitude
Parameters:
| Name | Type | Description |
|---|---|---|
jd |
JulianDay
|
The julian day |
# static exports.getEarthVelocity(jd) → {Coordinates3D}
Earth velocity (as a 3D vector), with respect to the barycenter of the solar system, in the equatorial
J2000.0 reference frame.
Parameters:
| Name | Type | Description |
|---|---|---|
jd |
JulianDay
|
The julian day |
The units are 10^-8 AstronomicalUnit per day.
Coordinates3D
# static exports.getEccentricity(jd)
Eccentricity of the orbit
See AA p.163 (and AA p.151)
Parameters:
| Name | Type | Description |
|---|---|---|
jd |
JulianDay
|
The julian day |
# static exports.getEclipticCoordinates(jd, equinox) → {EclipticCoordinates}
Heliocentric coordinates, see AA p.218, 219
Parameters:
| Name | Type | Description |
|---|---|---|
jd |
JulianDay
|
The julian day |
equinox |
Equinox
|
(optional) The equinox to be used: MeanOfTheDate (default) or StandardJ2000. |
# static exports.getEclipticLatitude(jd, equinox) → {Degree}
Heliocentric coordinates latitude, see AA p.218, 219
Corresponds to AA+ CAAEarth::EclipticLatitude
Parameters:
| Name | Type | Description |
|---|---|---|
jd |
JulianDay
|
The julian day |
equinox |
Equinox
|
(optional) The equinox to be used: MeanOfTheDate (default) or StandardJ2000. |
# static exports.getEclipticLongitude(jd, equinox) → {Degree}
Heliocentric coordinates longitude, see AA p.218, 219
Corresponds to AA+ CAAEarth::EclipticLongitude
Parameters:
| Name | Type | Description |
|---|---|---|
jd |
JulianDay
|
The julian day |
equinox |
Equinox
|
(optional) The equinox to be used: MeanOfTheDate (default) or StandardJ2000. |
# static exports.getEclipticLongitudinalRotation(jdStart, jdEnd, equinox) → {Degree}
Heliocentric coordinates longitudinal rotation between two dates.
Parameters:
# static exports.getEquatorialHorizontalParallax(jd) → {Degree}
Equatorial horizontal parallax
Parameters:
| Name | Type | Description |
|---|---|---|
jd |
JulianDay
|
The julian day |
# static exports.getFlatteningCorrections(height, lat) → {Number}
Computes the "rho*sin(phi')" and "rho*cos(phi')" quantities, due to Earth flattening.
See AA p 82
Parameters:
| Name | Type | Description |
|---|---|---|
height |
Meter
|
The observer heights above Earth surface. |
lat |
Degree
|
The observer's geographic latitude |
The quantities
Number
# static exports.getGeocentricEclipticCoordinates(jd) → {EclipticCoordinates}
Ecliptic coordinates
Parameters:
| Name | Type | Description |
|---|---|---|
jd |
JulianDay
|
The julian day |
# static exports.getGeocentricEclipticLatitude(jd) → {Degree}
Ecliptic latitude
Parameters:
| Name | Type | Description |
|---|---|---|
jd |
JulianDay
|
The julian day |
# static exports.getGeocentricEclipticLongitude(jd) → {Degree}
Ecliptic longitude
Parameters:
| Name | Type | Description |
|---|---|---|
jd |
JulianDay
|
The julian day |
# static exports.getGeocentricElongation(jd) → {Degree}
The geocentric elongation of the moon
Parameters:
| Name | Type | Description |
|---|---|---|
jd |
JulianDay
|
# static exports.getGeocentricEquatorialCoordinates(jd, obliquity) → {EquatorialCoordinates}
Geocentric equatorial coordinates
Parameters:
| Name | Type | Description |
|---|---|---|
jd |
JulianDay
|
The julian day |
obliquity |
Obliquity
|
The obliquity of the ecliptic: Mean (default) or True. |
- See:
-
- getApparentEquatorialCoordinates
# static exports.getGeocentricSemiDiameter(jd) → {Degree}
Geocentric Moon semi-diameter.
Error is less than 0.0005 arcsecond (see AA p391).
Parameters:
| Name | Type | Description |
|---|---|---|
jd |
JulianDay
|
The julian day |
# static exports.getIlluminatedFraction(jd) → {number}
The illuminated fraction of the Moon as seen from the Earth.
Between 0 and 1.
Parameters:
| Name | Type | Description |
|---|---|---|
jd |
JulianDay
|
The julian day |
number
# static exports.getLongitudeOfPerihelion(jd) → {Degree}
Longitude of perihelion
See AA p.151
Parameters:
| Name | Type | Description |
|---|---|---|
jd |
JulianDay
|
The julian day |
The longitude of perihelion
# static exports.getMeanAnomaly(jd) → {Degree}
Mean anomaly
Parameters:
| Name | Type | Description |
|---|---|---|
jd |
JulianDay
|
The julian day |
# static exports.getMeanElongation(jd) → {Degree}
Mean elongation
Parameters:
| Name | Type | Description |
|---|---|---|
jd |
JulianDay
|
The julian day |
# static exports.getMeanLongitude(jd) → {Degree}
Mean longitude
Parameters:
| Name | Type | Description |
|---|---|---|
jd |
JulianDay
|
The julian day |
# static exports.getMeanLongitudeAscendingNode(jd) → {Degree}
Mean longitude of the ascending node
Parameters:
| Name | Type | Description |
|---|---|---|
jd |
JulianDay
|
The julian day |
# static exports.getMeanLongitudePerigee(jd) → {Degree}
Mean longitude of perigee
Parameters:
| Name | Type | Description |
|---|---|---|
jd |
JulianDay
|
The julian day |
# static exports.getMeanObliquityOfEcliptic(jd) → {Degree}
Mean obliquity of the ecliptic.
The obliquity of the angle between the ecliptic (the plane of Earth orbit)
and the celestial equator (the project of Earth equator onto the spherical
sphere). The mean obliquity is NOT corrected for aberration and nutation of
the Earth.
Parameters:
| Name | Type | Description |
|---|---|---|
jd |
JulianDay
|
The julian day |
- See:
-
- getTrueObliquityOfEcliptic
# static exports.getNutationEquatorialAberration(jd, coords) → {EclipticCoordinatesCorrection}
Equatorial aberration due to nutation.
Warning: this is valid is not near the celestial poles (say < 1").
This is useful for stars, whose position are often given in equatorial coordinates.
For planets, use the `getApparentEquatorialCoordinates` methods instead.
See AA p 151, Equ 23.1
Parameters:
| Name | Type | Description |
|---|---|---|
jd |
JulianDay
|
The julian day |
coords |
EquatorialCoordinates
|
The equatorial coordinates |
The coordinates corrections in Arcsecond
EclipticCoordinatesCorrection
# static exports.getNutationInLongitude(jd) → {ArcSecond}
Nutation in longitude
Parameters:
| Name | Type | Description |
|---|---|---|
jd |
JulianDay
|
The julian day |
ArcSecond
# static exports.getNutationInObliquity(jd) → {ArcSecond}
Nutation in obliquity
Parameters:
| Name | Type | Description |
|---|---|---|
jd |
JulianDay
|
The julian day |
ArcSecond
# static exports.getPhaseAngle(jd) → {Degree}
The phase angle (angle Sun-Moon-Earth)
Parameters:
| Name | Type | Description |
|---|---|---|
jd |
JulianDay
|
The julian day |
# static exports.getPositionAngleOfTheBrightLimb(jd) → {Degree}
The position angle of the bright limb.
The position angle of the Moon's bright limb is the position angle of the midpoint of the illuminated limb of
the Moon, reckoned eastward from the North Point of the disk (not from the axis of rotation of the lunar globe).
Parameters:
| Name | Type | Description |
|---|---|---|
jd |
JulianDay
|
The julian day |
# static exports.getRadiusVector(jd) → {AstronomicalUnit}
Radius vector (distance from the Sun)
Corresponds to AA+ CAAEarth::RadiusVector
Parameters:
| Name | Type | Description |
|---|---|---|
jd |
JulianDay
|
The julian day |
# static exports.getRadiusVectorInKilometer(jd) → {Kilometer}
Radius vector (distance Earth-Moon) in kilometers!
Parameters:
| Name | Type | Description |
|---|---|---|
jd |
JulianDay
|
The julian day |
# static exports.getTimeOfMeanPhase(jd, phase) → {JulianDay}
The time of a given Moon phase.
Results are already corrected for the Sun's aberration and by the Moon's light-time.
Parameters:
# static exports.getTrueObliquityOfEcliptic(jd) → {Degree}
True obliquity of the ecliptic.
The obliquity of the angle between the ecliptic (the plane of Earth orbit)
and the celestial equator (the project of Earth equator onto the spherical
sphere). The true obliquity is equal to the mean obliquity corrected by
aberration and nutation of the Earth.
Parameters:
| Name | Type | Description |
|---|---|---|
jd |
JulianDay
|
The julian day |
- See:
-
- getMeanObliquityOfEcliptic
# static exports.horizontalParallax(jd) → {Degree}
Horizontal parallax
Parameters:
| Name | Type | Description |
|---|---|---|
jd |
JulianDay
|
The julian day |
# static exports.horizontalParallaxToRadiusVector(horizontalParallax) → {Kilometer}
Transforms a horizontal parallax into a radius vector
Parameters:
| Name | Type | Description |
|---|---|---|
horizontalParallax |
Degree
|
# static exports.radiusVectorToHorizontalParallax(radiusVector) → {Degree}
Transforms a radius vector into horizontal parallax
Parameters:
| Name | Type | Description |
|---|---|---|
radiusVector |
Kilometer
|
The radius vector |